1. School of Statistics, East China Normal University, Shanghai, China;
2. Department of Actuarial Studies and Business Analytics, Macquarie Business School, Macquarie University, Macquarie Park, Australia;
3. Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE, School of Statistics, East China Normal University, Shanghai, China;
4. Centre for Credit Card, Industrial Bank Co. Ltd, Shanghai, China